<?php
namespace TYPO3\CMS\Rsaauth;

/*
 * This file is part of the TYPO3 CMS project.
 *
 * It is free software; you can redistribute it and/or modify it under
 * the terms of the GNU General Public License, either version 2
 * of the License, or any later version.
 *
 * For the full copyright and license information, please read the
 * LICENSE.txt file that was distributed with this source code.
 *
 * The TYPO3 project - inspiring people to share!
 */

/**
 * This class contain an RSA key pair. Its purpose is to keep to keys
 * and transfer these keys between other PHP classes.
 *
 * @author Dmitry Dulepov <dmitry@typo3.org>
 */
class Keypair implements \TYPO3\CMS\Core\SingletonInterface {

	/**
	 * RSA public exponent (3 or 0x10001)
	 *
	 * @var int
	 */
	protected $exponent = 0;

	/**
	 * The private key
	 *
	 * @var string
	 */
	protected $privateKey = '';

	/**
	 * The public key modulus
	 *
	 * @var int
	 */
	protected $publicKeyModulus = 0;

	/**
	 * Checks if this key pair already has been provided with all data.
	 *
	 * @return bool
	 */
	public function isReady() {
		return $this->hasExponent() && $this->hasPrivateKey() && $this->hasPublicKeyModulus();
	}

	/**
	 * Retrieves the exponent.
	 *
	 * @return int the exponent
	 */
	public function getExponent() {
		return $this->exponent;
	}

	/**
	 * Sets the exponent
	 *
	 * Note: This method must not be called more than one time.
	 *
	 * @param int $exponent the new exponent
	 * @return void
	 * @throws \BadMethodCallException if the method was called more than one time
	 */
	public function setExponent($exponent) {
		if ($this->hasExponent()) {
			throw new \BadMethodCallException('setExponent() must not be called more than one time.', 1296062830);
		}

		$this->exponent = $exponent;
	}

	/**
	 * Checks whether an exponent already has been set.
	 *
	 * @return bool
	 */
	protected function hasExponent() {
		return $this->getExponent() !== 0;
	}

	/**
	 * Retrieves the private key.
	 *
	 * @return string The private key
	 */
	public function getPrivateKey() {
		return $this->privateKey;
	}

	/**
	 * Sets the private key.
	 *
	 * Note: This method must not be called more than one time.
	 *
	 * @param string $privateKey The new private key
	 * @return void
	 * @throws \BadMethodCallException if the method was called more than one time
	 */
	public function setPrivateKey($privateKey) {
		if ($this->hasPrivateKey()) {
			throw new \BadMethodCallException('setPrivateKey() must not be called more than one time.', 1296062831);
		}

		$this->privateKey = $privateKey;
	}

	/**
	 * Checks whether a private key already has been set.
	 *
	 * @return bool
	 */
	protected function hasPrivateKey() {
		return $this->getPrivateKey() !== '';
	}

	/**
	 * Retrieves the public key modulus
	 *
	 * @return int the public key modulus
	 */
	public function getPublicKeyModulus() {
		return $this->publicKeyModulus;
	}

	/**
	 * Sets the public key modulus.
	 *
	 * Note: This method must not be called more than one time.
	 *
	 * @param int $publicKeyModulus the new public key modulus
	 * @return void
	 * @throws \BadMethodCallException if the method was called more than one time
	 */
	public function setPublicKey($publicKeyModulus) {
		if ($this->hasPublicKeyModulus()) {
			throw new \BadMethodCallException('setPublicKey() must not be called more than one time.', 1296062832);
		}

		$this->publicKeyModulus = $publicKeyModulus;
	}

	/**
	 * Checks whether a public key modulus already has been set.
	 *
	 * @return bool
	 */
	protected function hasPublicKeyModulus() {
		return $this->getPublicKeyModulus() !== 0;
	}

}